The PCB analyses were quality assured by measuring the 
recovery of a surrogate compound (dibutylchlorendate) in each 
sample. The recovery of this compound was 70% +15 for the New 
London samples. 
2.7 In-situ Observations 
A team of diver/scientists conducted underwater 
observations at the New London Disposal Site to observe sediment 
surface conditions, identify species present and their relative 
abundances, observe faunal-substrate interactions, and provide 
photo documentation of conditions. Diver-operated epibenthic net 
samples (0.50m wide by 0.20m net height; lmm mesh; 15m tow) were 
taken at discrete points for enumeration of abundant smaller 
species associated with the sediment surface. Photo documentation 
was accomplished with diver-held 35mm camera and electronic flash 
equipment. 
Diver survey operations were conducted at the New London 
Disposal Site on 11 July 1985. A total of four dives were made at 
this time. These dives took place in an area in the southwest 
quadrant of the disposal site where mussel beds were prevalent, as 
well as in the northeast and northwest quadrants and over the NL- 
I disposal mound (Table 2-6). 
3.0 RESULTS 
3.1 Bathymetry 
The results of the August 1985 NLON Master bathymetric 
survey (Figure 3-1) depicts the bottom topographic features present 
at the New London Disposal Site. In general, the ambient bottom 
appeared to slope from a depth of approximately 16 meters in the 
northern portion of the area to a depth of 24 meters to the south. 
The area was relatively flat in an east/west direction except in 
the extreme southwest corner. The steep slope immediately 
southwest of the disposal site descended from an average depth of 
about 25 meters to a depth in excess of 59 meters over a horizontal 
distance of approximately 800 meters. The historic NL-I, NL-II, 
NL-III, and NL-RELIC mounds resulting from disposal operations 
during the late 1970's and early 1980's are clearly visible. 
A location just beyond the southwest boundary of the 
disposal site was evaluated for the deposition of dredged material 
from an anticipated project in the Thames River. This location 
was chosen primarily from data obtained during the REMOTS® survey 
described in Section 3.2. An initial examination of the REMOTS 
data showed that this location was a highly stressed area composed 
of a 2-3 cm layer of coarse material and disarticulated mussel 
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